[Nosographic picture of ischemic cardiopathy. Observations on the classification proposed by WHO].
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Angina Pectoris↗
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Spinal and cutaneous schwannomatosis is a variant form of type 2 neurofibromatosis: a clinical and molecular study.
OBJECTIVE: To delineate the clinical phenotype, molecular basis, and implications for screening in patients and families with multiple schwannomas not generally involving the cranium. METHODS: As part of a United Kingdom clinical and genetic study of type 2 neurofibromatosis (NF2) patients and families with multiple schwannomas who do not fulfil diagnostic criteria for NF2 have been identified. The clinical phenotype was studied in the extended families and molecular analysis was carried out at the NF2 gene locus on chromosome 22. RESULTS: Patterns of inheritance in five families with schwannomatosis are consistent with inheritance of an autosomal dominant gene. The consistency of phenotype, with relative sparing of the cranium, is constant in these families. However, families which initially seem to be indicative of schwannomatosis may develop into classic NF2 as shown by a sixth family. Many of the tumours found in these families were referred to as "neurofibroma" when they were clearly schwannomas. This difference in classification has major implications for the relative risk of each particular type of neurofibromatosis and neuropathological review may be important in some cases. Genetic linkage analysis in the two largest families is entirely consistent with primary involvement of the NF2 gene. CONCLUSIONS: Variant forms of neurofibromatosis have presented a dilemma in classification and determination of recurrence risks in families. Previous reports have suggested that schwannomatosis is a sporadic non-hereditary condition. Patients with multiple schwannomas are likely to have a variant form of NF2 and up to a 50% risk of passing on a gene predisposing to multiple schwannoma.
Adolescent↗
[Central nervous system lesions in neurofibromatosis. Clinical, MRI and histopathological correlations. A trial of classification].
The National Institute of Health Consensus Panel on Neurofibromatosis (NF) recently recognized 2 distinct forms of NF (NF-1 and NF-2) and stated that variant forms may exist. We selected 30 patients who fulfilled the criteria of NF-1 or whose condition was consistent with NF-2. All patients showed pathological magnetic resonance images (MRI), and in 19 cases confirmation was obtained from histopathology. We established correlations between the site and nature of the lesions on the one hand and the diagnostic criteria of NF on the other hand, there by hoping to contribute to a better knowledge and classification of neurofibromatosis. Nineteen patients had only intraparenchymatous lesions of the central nervous system (CNS) and fulfilled the criteria of NF-1; histopathological examination demonstrated pilocytic astrocytoma in 8 cases. Eleven patients showed only extra-axial lesions; 8 of them had criteria suggestive of NF-2, except for familial history. Pathological examination revealed either acoustic, pluriradicular of mixed schwannomas (7/8) or pluriradicular ganglioneuromas (1/8). Two patients had unilateral extra-axial pluriradicular cervical lesions and fulfilled the diagnostic criteria of NF-1; pathological examination revealed neurofibroma in both cases. One female patient had both intra- and extra-axial lesions that fulfilled the criteria of NF-1 and NF-2, suggesting the existence of a mixed form (NF-3).
Adolescent↗
[Central lesions in neurofibromatosis: clinical, MRI and histopathologic correlations. An attempted classification].
The National Institute of Health Consensus Panel on Neurofibromatosis (NF) recently recognized 2 distinct forms of NF (NF-1 and NF-2) and stated that variant forms may exist. We selected 30 patients who fulfilled the criteria of NF-1 or whose condition was consistent with NF-2. All patients showed pathological magnetic resonance images (MRI), and in 19 cases confirmation was obtained from histopathology. We established correlations between the site and nature of the lesions on the one hand and the diagnostic criteria of NF on the other hand, there by hoping to contribute to a better knowledge and classification of neurofibromatosis. Nineteen patients had only intraparenchymatous lesions of the central nervous system (CNS) and fulfilled the criteria of NF-1; histopathological examination demonstrated pilocytic astrocytoma in 8 cases. Eleven patients showed only extra-axial lesions; 8 of them had criteria suggestive of NF-2, except for familial history. Pathological examination revealed either acoustic, pluriradicular, peripheral or mixed schwannomas (7/8) or pluriradicular ganglioneuromas (1/8). Two patients had unilateral extra-axial pluriradicular cervical lesions and fulfilled the diagnostic criteria of NF-1; pathological examination revealed neurofibroma in both cases. One female patient had both intra- and extra-axial lesions that fulfilled the criteria of NF-1 and NF-2, suggesting the existence of a mixed form (NF-3).
Adolescent↗
Lymphomatoid papulosis: reappraisal of clinicopathologic presentation and classification into subtypes A, B, and C.
OBJECTIVES: To analyze clinicopathologic features of lymphomatoid papulosis and delineate the characteristics of histopathologic variants (types A, B, and C). DESIGN: Retrospective nonrandomized study. SETTING: University-based dermatologic referral center. PATIENTS: Eighty-five patients with lymphomatoid papulosis. Clinical data and 1 or more biopsy specimens were available for review in all cases. When possible, immunophenotypic and molecular analyses were carried out. RESULTS: Of these patients, 78 presented only 1 histopathologic subtype of lymphomatoid papulosis (64 had type A, 3 had type B, and 11 had type C). The last 7 patients presented more than 1 subtype (1 had A and B, 5 had A and C, and 1 had A, B, and C). Two patients had regional lymphomatoid papulosis, an unusual clinical presentation characterized by groups of lesions localized to 1 anatomic region. We observed, we believe for the first time, that some histopathologic patterns, ie, follicular mucinosis (n = 1), syringotropic infiltrates (n = 1), epidermal vesicle formation (n = 2), and syringosquamous metaplasia (n = 1), were associated with lymphomatoid papulosis. A distribution along hair follicles, or follicular lymphomatoid papulosis, was observed in 5 biopsy specimens. A bandlike rather than a wedge distribution of the infiltrate was seen in 5 specimens from patients with lymphomatoid papulosis type A. Of 8 patients who had associated lymphoid malignancies, 4 had Hodgkin disease and 4 had mycosis fungoides. CONCLUSIONS: Lymphomatoid papulosis is a cutaneous disorder with multiple clinicopathologic features. Differentiating between mycosis fungoides and anaplastic large cell lymphoma may be very difficult and sometimes impossible. In the spectrum of CD30(+) cutaneous lymphoproliferative disorders, boundaries between these 2 entities are not clear-cut.
Adult↗
Pathological variants of basal cell carcinoma.
Although the pathological features of basal cell carcinoma are well known, there is no generally agreed classification of the subtypes of this tumour. Certain histological subtypes are associated with indistinct clinical margins, inadequate primary excisions and frequent recurrences, and these must be recognized and reported by pathologists so that the most appropriate therapy is given. The current classification of subtypes of basal cell carcinoma is discussed and reference made to the rarer forms of this tumour.
Biopsy, Needle↗
[Histological classification of chronic glomerular diseases].
The various clinicopathological forms of primary glomerulonephritis (GN) in humans include lipoid nephrosis with its histological variants (minimal change disease, focal segmental glomerular sclerosis, diffuse mesangial proliferation, collapsing glomerulopathy), membranous GN, IgA nephropathy, membranoproliferative GN (type I and type II) and crescentic GN. Each of these entities is characterised by pathological, clinical, and immunological features. Although the precise aetiology of primary GN remains unknown, progress has been recently achieved in the understanding of the mechanisms of the glomerular lesions and of their progression. Early diagnosis may lead to adequate treatment and prevention of progressive glomerular damage.
Adult↗
Serotyping HIV-1 with V3 peptides: detection of high avidity antibodies presenting clade-specific reactivity.
The main objective of the present study was to assess the specificity and sensitivity of a modified assay using short synthetic peptides of the V3 region of HIV-1 gp120, which is the main target for neutralizing antibodies. Results from an enzyme immunoassay (EIA) employing a panel of synthetic peptides of HIV-1 subtypes and using urea washes to detect high avidity antibodies (AAV3) were compared with those obtained by the heteroduplex mobility assay and DNA sequencing. The EIA correctly typed 100% of subtype B (sensitivity = 1.0; specificity = 0.95), 100% of HIV-1 E samples (sensitivity = 1.0; specificity = 1.0), and 95% of subtype C specimens (sensitivity = 0.95; specificity = 0.94). In contrast, only 50% of subtype A (sensitivity = 0.5; specificity = 0.95), 60% of subtype D (sensitivity = 0.6; specificity = 1.0), and 28% of subtype F samples (sensitivity = 0.28; specificity = 0.95) were correctly identified. This approach was also able to discriminate in a few samples antibodies from patients infected with B variants circulating in Brazil and Thailand that reacted specifically. The assays described in this study are relatively rapid and simple to perform compared to molecular approaches and can be used to screen large numbers of serum or plasma samples. Moreover, the classification in subtypes (genotypes) may overestimate HIV-1 diversity and a classification into serotypes, based on antigenic V3 diversity or another principal neutralization domain, may be more helpful for vaccine development and identification of variants.
Amino Acid Sequence↗
Classification of contaminants by mode of action based on in vitro assays.
A concept for toxicity assessments based on in vitro assays of variant levels (i.e., from whole cells to isolated enzymes) is presented. Due to the complexity of organisms of different species, it is evident that no single in vitro test can represent the entire spectrum of toxic potency of chemicals, rather a carefully designed battery of tests has to be employed to account for the various targets attacked in organisms yielding the different modes of action. Cytotoxicity tests like the Neutral-Red Assay predominantly reflect non-specific toxicity, which can be modelled according to a log Pow dependent baseline QSAR. Specific toxicants (e.g., decouplers, acetylcholinesterase inhibitors or photosystem II inhibitors) may be identified based on according in vitro tests and eventually modelled by the respective mode of action related QSARs employing also, e.g., steric or polarizability descriptors to account for specific interactions. The complementation and partial replacement of in vivo (eco)toxicological testing by in vitro assays depends on two criteria: (a) the sensitivity of the tests to reliably detect environmentally relevant concentrations of toxicants and (b) the specificity of the assays to provide an unambiguous classification of toxicants by modes of action: the pattern of interaction with the various targets allows to recognize those compounds of specific effects that frequently occur as outliers in QSAR analyses.
Acetylcholine↗
Genetic variants of human erythrocyte glucose-6-phosphate dehydrogenase: new characterization data obtained by multivariate analysis.
Thirteen variables used in the course of characterization of G6PD variants from forty-one individuals have been submitted to multivariate factorial and cluster analysis. Because of the diagrammatic representation of the analysis, two main findings were made possible. Firstly, the three-dimensional plot of the experimental data gives the advantage of a model of classification which is closely related to the ethnogeographical origin of the subjects, and to the clinical and haematological incidence of the G6PD variants. Secondly, cluster analysis visualizes the distance between the G6PDs examined. In this respect, it was determined that three local original variants associated with acute haemolytic anaemia showed a close relationship and belonged to the same cluster (Gd(-) Toulouse, Gd(-) Muret and Gd(-) Colomiers). Conversely, two non-haemolytic variants (G6PD Luz Saint Sauveur and Lozère) were found to be linked in another remote cluster. The procedure developed in this work promotes a new approach to G6PD characteristics in human genetic studies.
Adolescent↗
Hematopathological features of acute erythremia (morbus Di Guglielmo). A contribution to the classification and differential diagnosis of erythroid neoplasias.
Classification and differential diagnosis of erythroid neoplasias still are a matter of discussion. Eleven cases of primary acute erythremia were diagnosed between 1981 and 1984 at the Institute of Pathology, University of Kiel. Erythremia represented 0.5% of all hematological diagnoses and 1.0% of the myeloproliferative disorders. The male-to-female ratio was 1:1. Incidence peaked in the 7th decade. Evaluation of clinical data, of cytological and histological findings in blood and bone marrow, and of occasional immunophenotyping of blast cells (anti-glycophorin A+) revealed two variants of acute erythremia: a first, blastic one and a second, more differentiated form. Acute erythremia must be strictly distinguished from mixed erythroid/myeloid erythroleukemia and from secondary erythroid neoplasias, especially the erythremic 'blast crisis' of chronic myeloid leukemia or polycythemia vera rubra. Distinguishing the myelodysplastic variant of sideroblastic anemia from anerythremic acute erythremia can be extremely difficult. We discuss the differential diagnosis and classification of erythroid neoplasias based upon reproducible hematological criteria to facilitate the gathering and comparison of epidemiological and clinical data on these rare malignancies.
Acute Disease↗
[Numerical classification of viruses within families].
The possibility of using cluster analysis for allocation of viruses into groups having a taxonomic rank below the family was studied. As a result, a modified variant of cluster analysis is proposed which may be used for investigation of similarities and differences among viruses within individual families and formation of groups corresponding to those of a lower taxonomic rank than the family. The use of this modified variant of cluster analysis allowed the authors to distinguish groups in the majority of the families studied corresponding to ICTV genera. The data have been obtained suggesting the necessity of changing the taxonomic rank of some virus groups. The above studies have shown the possibility of developing numerical classification of viruses at the subfamily and genus levels, in other words, a single hierarchical numerical classification of viruses.
Adenoviridae↗
[Rhabdoid meningioma. A new malignant subtype].
Of the numerous morphological variants of meningiomas only few, and among these the rhabdoid meningioma, have prognostic importance. Rhabdoid meningiomas were described for the first time in 1998 as an unusual variant with increased proliferative activity. In 2000 they have been included in the revised WHO classification of tumours of the CNS as a subtype of meningiomas with increased risk of recurrence and more aggressive growth, corresponding to WHO grade III. We report the case of a rhabdoid meningioma in a 21-year-old woman presenting as a intracerebral tumour mimicking an oligodendroglioma. The tumour showed features of a meningioma and a rhabdoid morphology with angiomatous components and was considered to be a rhabdoid meningioma. After surgery a small residual tumour remained. The patient received postoperative radiotherapy resulting in regression of the residual tumour in control examinations after 4 and 8 months. Using the presented case we discuss the differential diagnosis and prognostic significance of recognition of a rhabdoid meningioma.
Brain Neoplasms↗
Sclerosing rhabdomyosarcoma in childhood: case report and review of the literature.
Rhabdomyosarcoma is the most common soft tissue malignancy in children but is rare in adults. The latest World Health Organization classification of soft tissue tumors recognizes embryonal, alveolar, and pleomorphic rhabdomyosarcomas. More recently, a sclerosing variant of rhabdomyosarcoma has been recognized and reported in seven adult patients. We describe a pediatric case of sclerosing rhabdomyosarcoma presenting as a sacral mass in a 3-year-old girl. Morphologically, the tumor showed a prominent sclerosing hyaline matrix and demonstrated pseudovascular and microalveolar architectural foci. Focal positivity was seen with desmin, smooth muscle actin, and myogenin. MyoD1 showed uniform diffuse nuclear staining. Fusion transcripts were not demonstrated by reverse transcriptase-polymerase chain reaction analysis. The histology, immunohistochemistry, and molecular genetics matched those reported in the seven adult cases of sclerosing rhabdomyosarcoma. This is the first case report, to our knowledge, of this rare tumor arising in the pediatric age group, and we compare the features with those reported in adult sclerosing rhabdomyosarcoma.
Child, Preschool↗
Cytogenetics of three cases of ANLL M2 and M4. Involvement of chromosomal region 8q22 in all three but 21q22 in only one.
Cytogenetic investigation of the bone marrow of two patients with acute nonlymphocytic leukemia (ANLL), French-American-British Cooperative group (FAB) classification M2, revealed a translocation (8;22)(q22.1;q13.3), without involving chromosome 21, and a variant translocation (8;21)(q22;q22). These findings, together with a del(8)(q22) found in a patient with refractory anemia, erythroblastic (RAEB)-t with progression to acute myelogenous leukemia (AML)-M4, are discussed in relation to the possible role of abnormalities of chromosomes 8 and 21 in the oncogenesis of ANLL M2 and M4.
Child, Preschool↗
Description and genomic characterization of Aquipuribacter aurantiacus sp. nov., isolated from saline lake sediment.
Strains MA13-6T and MA13-13, two Gram-stain-positive, aerobic, short rod-shaped actinobacteria, were isolated from a saline lake in Ngari Prefecture, Xizang Autonomous Region, China. Phylogenetic analysis based on 16S rRNA gene sequences indicated that these two strains belonged to the genus Aquipuribacter, with the closest relationship to Aquipuribacter hungaricus IV-75T (98.47% sequence similarity) and Aquipuribacter nitratireducens AMV4T (97.36% sequence similarity). Phylogenetic analysis based on genomes further confirmed their classification as a distinct cluster within the genus Aquipuribacter. The average nucleotide identity and digtal DNA-DNA hybridization values between these two strains and their closest relative Aquipuribacter hungaricus IV-75T, were 82.44-82.49% and 23.00%, respectively, clearly indicating that strains MA13-6T and MA13-13 represent a novel species. The 16S rRNA gene sequence similarity, average nucleotide identity and digital DNA-DNA hybridization values between these two strains were 99.79%, 99.97% and 99.40%, respectively, unequivocally confirming their classification within the same species. However, DNA fingerprinting analysis distinguished them as non-clonal variants. The polar lipids comprised phosphatidylglycerol, two unidentified phospholipids, two unidentified glycolipids, and two unidentified lipids. The predominant respiratory quinone was MK-10 (H4). The major fatty acids were anteiso-C15:0, C18:1ω9c, isoC16:0 and anteiso-C17:0. The cell wall diagnostic diamino acid was meso-diaminopimelic acid. Based on phylogenetic analyses combined with phenotypic and chemotaxonomic characterization, strains MA13-6T and MA13-13 represent a novel species of the genus Aquipuribacter, for which the name Aquipuribacter aurantiacus sp. nov. is proposed. The type strain is MA13-6T (=MCCC 1K10045T = KCTC 59572T).
Phylogeny↗
Oromandibular-limb hypogenesis syndromes: a case of aglossia with an intraoral band.
Oromandibular and limb syndromes feature primarily in sporadic case reports because of their low incidence. They include Moebius syndrome, aglossia-adactylia syndrome, Hanhart syndrome, glossopalatine ankylosis syndrome, limb deficiency-splenogonadal fusion syndrome and Charlie M. syndrome. There is confusion in the classification of these patients because of the associated anomalies and the frequency of overlapping features. This paper presents a patient with oromandibular malformations associated with major defects in the upper and lower limbs. Aglossia in the presence of an intraoral band is a peculiar association demanding classification. This case confirms that aglossia-adactylia syndrome and the glossopalatine ankylosis syndrome are variants along a spectrum.
Abnormalities, Multiple↗
The maxillary second molar: variations in the number of roots and canals.
A retrospective study was undertaken of 520 completed endodontic treatments of maxillary second molar teeth which were selected from a specialty endodontic practice. Radiographs were reviewed and studied, a classification of antomical root and canal variations was devised, and the frequency with which each variant occurred was recorded. There were six variants which occurred frequently enough to be considered as separate anatomic categories and their frequency of occurrence is illustrated. The six variants found in the study and their frequency of occurrence are as follows: (1) three separate roots and three separate canals (56.9%); (2) three separate roots and four canals (two in the mesiobuccal root) (22.7%); (3) three roots and canals whose mesiobuccal and distobuccal canals combine to form a common buccal with a separate palatal (9%); (4) two separate roots with a single canal in each (6.9%); (5) one main root and canal (3.1%); and (6) four separate roots and four separate canals including two palatal (1.4%). Clinical examples of these deviant variations are also presented.
Dental Pulp Cavity↗